1. Field of the Invention
The present invention relates to a disk loading device and a cartridge of an apparatus for recording and reproducing information in a recording medium such as a disk by using optical means.
2. Description of the Related Art
Recently, optical disk apparatuses are being widely used for audio discs, video discs and computer data memory devices.
Optical disks are classified into those contained in a cartridge to be recording and reproduced, used mainly in data storage, and disks to be reproduced only, used in a bare state, such as music CD and CD-ROM. Along with the progress of the multimedia, digitization of AV appliances and enhancement of AV functions in computer are advanced simultaneously, and the optical disks are required to function as a digital disk to be used widely in AV appliances and computers alike.
Further, not only the AV appliances but also personal computers are more and more reduced in size, and thus the optical disk apparatus is demanded to be further thinner.
In this background, regarding the optical disk apparatus, a thin type apparatus applicable to multiple formats of media is strongly demanded.
Hitherto, however, between the disk contained in the cartridge and the bare disk, the loading method for loading the disk into the apparatus is different, and various exclusive devices were needed.
Conventional devices are described below while referring to the drawings.
First, the loading mechanism of an optical disk apparatus for a cartridge used mainly as data memory device is explained with reference to the accompanying drawings.
Generally, in such optical disk apparatus, after inserting a cartridge into the apparatus, this cartridge must be moved in the direction of a spindle motor and an optical pickup, and the disk must be put on the turntable to be set in a recording or a reproducing state.
FIG. 49 is a prior art perspective view showing a structure of a disk loading mechanism, FIG. 50 is a side view showing its operation, and FIG. 51 is a schematic view showing the dimensional relation in the thickness direction within the device.
In FIG. 49 and FIG. 50, a cartridge 201 is inserted into a cartridge holder 202 from the front side of the disk loading device (hereinafter called the device). At this time, a shutter 201a of the cartridge 201 slides as being engaged with a shutter opener 210 assembled in the cartridge holder 202, and the recording and reproducing region of the disk in the cartridge 201 is exposed. At both sides of the cartridge holder 202, four guide rollers 203 are provided, and they are inserted into guide grooves 205 provided at both sides of a slider 204, so as to be movable by dimension d only in the vertical direction along a guide pole 207 planted on a chassis 206.
The slider 204 is provided so as to be slidable by dimension S in the direction of arrow A along a guide pin 208 planted on the chassis 206 in such a shape as to nip the cartridge holder 202 from beneath. The slider 204 is always thrust against the chassis 206 in direction A by means of a slider spring 209, and it is arrested, in initial state, by a lock arm (not shown) so that the slider spring 209 may be stopped in the maximum extended state (see FIG. 50(a)).
A damper 214 is rotatably held by a support arm 215, and is disposed at a position of an upper central opening 202a of the cartridge holder 202, so as to confront a turntable 212 on a disk motor 211. The damper 214 and turntable 212 attract each other by the attracting force of a magnet and a magnetic piece incorporated respectively.
The support arm 215 is rotated by a cam (not shown) provided in the slider 204 depending on its position, and moves up and down the damper 214. In initial state, the damper 214 is lifted to a position so as not to interfere with the cartridge 201 to be inserted (see FIG. 50(a)).
The lock arm is, when the cartridge 201 is inserted, pushed by a corner of the cartridge and is released. When the lock arm is released, the slider 204 slides in direction A by means of the slider spring 209, and the guide roller 203 moves along the guide groove 205, so that the cartridge holder 202 is moved by dimension d only in the direction (arrow B) of the chassis 206. At the same time, the support arm 215 is rotated by the slider 204, and the damper 214 is moved in the direction of the turntable 212. As the cartridge 201 descends, the disk in the cartridge 201 is put on the turntable 212, and is attracted by the damper 214 from above to be installed in a rotatable state, and is brought closer to the optical pickup 213 within a distance for recording and reproducing (see FIG. 50(b)).
When taking out the cartridge 201 from the device, the slider 204 is pulled back against the pulling force of the slider spring 209 by means of a loading motor 216, and the clamper 214 and cartridge holder 202 are raised to the position of the initial state. As a result, the disk is separated from the turntable 212, so that it is ready to take out the cartridge 201.
As shown in FIG. 51, when inserting the cartridge 201, a distance more than the thickness of the cartridge 201 (dimension D) is required between the turntable 212 and clamper 214.
Next, a loading mechanism of a prior art optical disk apparatus for bare disks such as music CD or CD-ROM is described while referring to FIG. 52 and FIGS. 53(a)-(c).
In FIG. 52 and FIG. 53, reference numeral 253 is a main chassis, which comprises a disk motor 256, a turntable 258 mounted on its shaft, a center cone 258a on the turntable 258 engaged with a central hole 245a of a disk 245 which is a recording disk, a head 243 mounting a coil 243a for linear motor slidably disposed in Y1-Y2 direction by a guide shaft 255, and a magnetic yoke 254 for linear motor. A hole 253b for rotary support point is provided at one end 253a of the main chassis 253, and a rotary support shaft 251 is passed in this hole 253b.
Similarly, at one end 247a of the clamp lever 247, a hole 247b for rotary support point is provided, and the rotary support shaft 251 is also passed in this hole 247b, and this rotary support shaft 251 is fixed on a protrusion 252 in a casing 242.
A tray 241 is provided inside of the casing 242 so as to move parallel in Y1-Y2 direction by motion in engagement between a rack 241a formed on the back side and an output gear of a loading motor 257 in which a reduction gear unit is provided. In the tray 241, moreover, a pan-shaped dent 246 is formed for mounting and holding the disk 245. When this dent 246 is formed in two steps, a small disk 260 can be also mounted.
Further, a cam 250 is engaged with the rear parts of the main chassis 253 and clamp lever 247. This cam 250 is driven by a geared motor 249. Depending on the position of rotation of the cam 250, the main chassis 253 and clamp lever 247 are designed to rotate about the rotary support shaft 251 to approach or depart each other. Reference numeral 240 is an insert port, 241b is an opening, and 248 is a clamper. The operation of the loading motor 257 and geared motor 249 is executed by ordinary microcomputer control. The position of the cam 250 or tray 241 driven by each motor is detected by an ordinary microswitch or the like. Their detail is not illustrated and explanation is omitted.
FIGS. 53(a), (b), (c) show the operation of the disk loading device of this prior art.
That is, when using the disk 245 in a disk recording and reproducing apparatus, when an eject/load switch 261 is pressed, the tray 241 is moved in Y2 direction by driving force of the loading motor 257 by microcomputer control, and comes out of the casing 242 to be in a state as shown in FIG. 53 (a). At this time, the clamp lever 247 and main chassis 253 are at mutually departed positions from the rotary support shaft 251.
In this state, when the disk 245 is put in the dent 246 of the tray 241 and the eject/load switch 260 is pressed, the tray 241 is transferred parallel into the casing 242 through the insert port 240 by driving force of the loading motor 257 to be in a state as shown in FIG. 53(b).
Consequently, the cam 250 rotates, and the clamp lever 247 and main chassis 253 approach each other on the rotary support shaft 251 as shown in FIG. 53(c), and the disk 245 is nipped between the damper 248 and the turntable 258 of the disk motor 256, and is engaged with the center code 258a to be in rotatable state. In this state, information in the disk 245 is reproduced or recorded by the head.
When taking out the disk 245 from the device, the operation in exactly reverse procedure is carried out.
In the disk loading device of such conventional disk apparatus, however, the loading device is exclusive for cartridge in the first prior art, and exclusive for the bare disk in the second prior art, and the following problems occur in the disk loading device handling both cartridge and bare disk (collectively called media hereinafter).
That is, immediately after loading of media in the loading device, it cannot be judged whether it is cartridge or bare disk, or if it is loaded correctly in the device, so loading operation is required before driving it, and the device may be broken due to insertion of foreign matter or wrong insertion.
Generally, since prevention of insertion of cartridge in wrong direction or wrong side depends on the shape of the cartridge, in the loading device capable of mounting plural types of cartridges, it is difficult to prevent wrong insertion of a cartridge.
Besides, if the shutter provided in the panel has no regulation of opening, when a bare disk is stored in the opening of the tray or cartridge holder provided for attaching or detaching the cartridge, if the shutter is opened, it is likely to touch the bare disk rotating at high speed, and the user may be injured.
Further, due to the effect of deflection of the shutter provided in the cartridge, the distance between the disk contact part of the cartridge opening and the disk stored in the cartridge is shortened, and there is a possibility of contact with the cartridge during rotation of the disk.
Recently, on the other hand, aside from the recording and reproducing apparatus having the exclusive disk tray and the recording and reproducing apparatus having the exclusive cartridge tray, a recording and reproducing apparatus having a tray capable of mounting disks and cartridges selectively has been proposed.
In this recording and reproducing apparatus (hereinafter called the compatible loading device), a disk mounting section and a cartridge mounting section are disposed on the tray, and when the cartridge is put on the tray, it is desired that the tray is firmly held in the loading device, and when pushing in the tray, it is desired to be manipulated by a small effort. When forcing out the media by force in a power off state, it is desired that the tray discharge force is small.
In the conventional compatible loading device, however, since such tray manipulating load is determined by the gear ratio of the drive system of the loading device and the loading motor, it was difficult to optimize the tray manipulating load depending on the type of the media, and the power on or off state.
In the compatible loading device, moreover, since the casing (fixed side) mounted on the personal computer and the recording and reproducing unit of cartridge and built-in disk (movable side) are separated by a damper, and when mounting on the personal computer, a gap is opened to absorb vibration due to impact between the opening of the casing and the movable side due to restriction of the outer structure of the device, and invasion of dust into the loading device is admitted, and also the pressure is negative inside the device due to rotation of the disk motor (spindle motor or the like), and dust or smoke is sucked toward the center of the motor, and such dust or smoke causes contamination of the recording and reproducing side of the disk or the lens over a long period of time.
Generally, in the drive system gear train of the tray, it is desired to use spur gears in consideration of the gear transmission efficiency, and when a spur gear train is used, the reduction ratio must be higher, and a spur gear of relatively large diameter must be used, but when a spur gear of large diameter is used, it is hard to reduce the size and thickness of the disk loading device. Accordingly, a worm gear is used in order to obtain a high reduction ratio in a narrow space.
In such a conventional disk loading device, however, aside from transfer of tray by driving the loading motor in the driving source, the tray may be transferred by a driving source other than the loading motor (transfer by manual operation), and the loading motor and the drive system may be operated by force by this driving source, and in this case, by such operation, arrest of rotation of the loading motor or damage may be induced by the force in reverse axial direction from the direction applied to the worm gear.
If trouble occurs in rotary motion in the loading motor or around the drive system, it is necessary to draw out the tray smoothly so that the media in the loaded state may be taken out easily.
Still more, for further reduction in size and thickness of the disk loading device, there were problems in optimization of the shape of the worm gear and engagement with the drive gear, and reduction of structural space of the drive gear train.